FIG. 3 shows a conventional two-pole universal motor which comprises a stator and a rotor. The stator comprises a C-shaped stator core and winding wound on the stator core. When the winding is electrified, the stator forms two magnetic poles. A conventional four-pole universal motor (not shown) usually needs an enclosed stator core which may be divided into two C-shaped parts respectively located at opposite sides of the rotor. Thus a two pole motor can not operate as a four pole motor and the four pole motor is limited in how close the output shaft can be to a wall of an appliance in which the motor is fitted due to the presence of the stator core surrounding the rotor.
The present invention is desired to provide a new type of stator core and universal motor using the type of stator core.